Kamata, Ota, Tokyo
Kuroyu Onsen Yu City Kamata
A convenient Kamata stop for natural black water, sauna and a cold bath at sento prices. The natural spring is in the semi-outdoor black-water pool; the other pools should not all be assumed to use spring water.
Facility photos
Check before bathing
- Opening hours
- Bathing 11:00–24:00; closed Tuesdays. Adult entry ¥600. Hands-free set ¥850; entry plus sauna ¥900; sauna with hands-free set ¥980. Common-ticket holders can add sauna for ¥370. The adjacent YCK Hall has separate hours and is usually closed Mondays and Tuesdays.
- Access
- About a 5-minute walk from the east exit of JR Kamata Station. Six free parking spaces are listed, but some are on a sloped semi-basement level; check vehicle clearance and leave the key at reception as directed.
- Tattoo policy
- The current main page does not give a clear standing tattoo rule; ask the facility before visiting if needed.
Spring & water temperature
- Spring-source temperature
- Not published by the operator. A dated 2026 secondary transcription gives about 18°C, but this is not an official current figure.
- Bathing temperature
- White and black-water baths about 41–42°C; cold bath about 14–18°C. These are bath settings, not source temperatures.
- Spring source
- The operator describes natural black water drawn from about 120 m underground; a formal source name is not published.
- Spring classification
- Natural black spring. Secondary 2026 field transcriptions commonly describe a sodium bicarbonate cold mineral spring, but the operator has not published a complete current analysis sheet.
- pH
- Not published by the operator; a dated 2026 secondary transcription gives about 8.7, with older sources differing.
- Flow rate
- Not published by the operator; a dated 2026 secondary transcription gives about 127 L/min, with older values differing.
- Water handling
- Natural black water is confirmed in the semi-outdoor black-water bath. Pool-specific water addition, heating, circulation and disinfection details are not published; the white-water baths and other pools are not all treated as natural spring water.
Free parking is limited and some spaces have a low sloped entry. The bathhouse does not provide shampoo or body wash free of charge.
How to read a bath profile
Spring-source temperature and actual bathing temperature are kept separate. Each score is shown independently for comparison rather than collapsed into one overall score.
